System and method for clock synchronization and time transfer between quantum orchestration platform elements

Abstract

A quantum orchestration platform (QOP) comprises a collection of processing units and analog components that produce synchronized analog pulses, readouts, and computations that may be used for operations with qubits. All processing units of the QOP are synchronized with minimal skew via time processing over one or more sync cables that interconnect the processing units.

What is claimed is: 
     
         1 - 7 . (canceled) 
     
     
         8 . A system for time transfer comprising:
 a first processing unit comprising a first time counter that increments according to a first clock;   a second processing unit comprising a second time counter that increments according to a second clock;   a cable coupled between the first processing unit and the second processing unit, wherein:
 the first processing unit is operable to send a first message to the second processing unit via the cable, wherein the first message comprises a first timestamp according to the first time counter; 
 the second processing unit is operable to send a second message to the first processing unit via the cable, wherein the second message comprises a second timestamp according to the second time counter; 
 the second processing unit is operable to generate a first timestamp difference according to the first message as received and the second time counter upon arrival of the first message; 
 the first processing unit is operable to generate a second timestamp difference according to the second message as received and the first time counter upon arrival of the second message; 
 the first clock is adjustable according to the first timestamp difference and the second timestamp difference; and 
 the second clock is adjustable according to the first timestamp difference and the second timestamp difference. 
   
     
     
         9 . The system of  claim 8 , wherein the first clock and the second clock are both at a common frequency. 
     
     
         10 . The system of  claim 8 , wherein a quantum orchestration platform (QOP) comprises the first processing unit and the second processing unit. 
     
     
         11 . The system of  claim 8 , wherein a phase difference between the first clock and the second clock is determined according to Manchester encoding. 
     
     
         12 . The system of  claim 8 , wherein the first processing unit and the second processing unit are operable to communicate an operation over the cable. 
     
     
         13 . The system of  claim 12 , wherein the operation is a phase recalibration. 
     
     
         14 . The system of  claim 12 , wherein a polarity of the cable indicates whether the first processing unit is transmitting the operation or receiving the operation. 
     
     
         15 . The system of  claim 8 , wherein the first processing unit is operable to command the second processing unit to start, stop, pause or resume execution of an operation. 
     
     
         16 . The system of  claim 15 , wherein the command is associated with a particular timestamp. 
     
     
         17 - 36 . (canceled) 
     
     
         37 . A method for time transfer comprising:
 generating, at a first processing unit, a first local time that increments according to a first clock;   generating, at a second processing unit, a second local time that increments according to a second clock;   forwarding, via a cable, a first message from the first processing unit to the second processing unit, wherein the first message comprises a first timestamp according to the first local time;   generating, at the second processing unit, a first timestamp difference between the first timestamp and the second local time;   forwarding, via the cable, a second message from the second processing unit to the first processing unit, wherein the second message comprises a second timestamp according to the second local time;   generating, at the first processing unit, a second timestamp difference between the second timestamp and the first local time;   adjusting, via a variable delay unit, one or both the first clock and the second clock, wherein the adjusting is according to the first timestamp difference and the second timestamp difference.   
     
     
         38 . The method of  claim 37 , wherein:
 the first clock and the second clock are both at a common frequency,   generating the first timestamp difference comprises subtracting the first timestamp from an arrival timestamp, and   the arrival timestamp is generated according to the second local time.   
     
     
         39 . The method of  claim 37 , wherein a quantum orchestration platform (QOP) comprises the first processing unit and the second processing unit. 
     
     
         40 . A system, comprising:
 a first processing unit comprising a first clock and a first counter incrementing according to the first clock;   a second processing unit comprising a second clock and a second counter incrementing according to the second clock; and   a communication interface coupled between the first processing unit and the second processing unit, wherein:
 the first processing unit is operable to transmit a first message comprising a first counter value to the second processing unit, 
 the second processing unit is operable to determine a first offset value according to the first counter value and the second counter upon receipt of the first message, 
 the second processing unit is operable to transmit a second message comprising a second counter value to the first processing unit, 
 the first processing unit is operable to determine a second offset value according to the second counter value and the first counter upon receipt of the second message, and 
 one or both of the first clock and the second clock are adjustable according to the first offset value and the second offset value to synchronize the first counter and the second counter. 
   
     
     
         41 . The system of  claim 40 , wherein the communication interface comprises a bidirectional cable. 
     
     
         42 . The system of  claim 40 , wherein the first clock and the second clock operate at a common nominal frequency. 
     
     
         43 . The system of  claim 40 , wherein the synchronization comprises determining a round-trip delay according to the first offset value and the second offset value. 
     
     
         44 . The system of  claim 40 , wherein the adjustment to one or both clocks is performed via a variable delay module within the respective processing unit. 
     
     
         45 . The system of  claim 40 , wherein a quantum orchestration platform comprises the first processing unit and the second processing unit. 
     
     
         46 . The system of  claim 40 , wherein the system comprises a timing control module operable to align operations according to a plurality of synchronized counter values.